Heretofore, there are known as transparent resins, a polymethylmethacrylate resin, a polycarbonate resin, a polystyrene resin, an alicyclic olefin polymer (for example, see Patent Document 1), and an epoxy resin. Such transparent resins have been industrially manufactured in a large scale, and used in great quantities in various fields, because of their good transparency. Further, such transparent resins have been used as glass substitutes by taking advantages, in addition to their good transparency, of lightweight properties, cutting properties, and abradability. Further, while reflecting recent trends of lightness, thinness, shortness, and smallness, the resins tend to be used in many cases at a place which is more closer to heat sources than before. This requires the transparent resins to have higher heat resistance in addition to optical properties such as light transmittance. However, heat resistance of the above-mentioned transparent resins is not fully sufficient. For example, even the polycarbonate resin, which being said as having the highest heat resistance of the above transparent resins, has a glass transition temperature, which is an index of its heat resistance, of about 150° C. For this reason, there has been a need for the development of a new transparent resin having higher heat resistance.
Specifically, poly(meth)acrylate-based polymers such as polymethylmethacrylate, and polycarbonate-based polymers have already been used as a material of a resin for an optical component. Meanwhile, polymethylacrylate, which is one of the above poly(meth)acrylate-based polymers, is inferior in properties including heat resistance, thermal stability, chemical resistance, and solvent resistance, and has a high water absorption property and low water resistance. Therefore, polymethylacrylate was not able to be used in the field where such properties were demanded. In addition, polymethylmethacrylate is used as a material of a resin for an optical component as described above, but there was a problem that polymethylmethacrylate was not applicable to the field where heat resistance and thermal stability were especially demanded.
As a method of improving the above-mentioned, heretofore known problem involved in the poly(meth)acrylate-based polymers in the field of the material of a resin for an optical component, a method that employs a homopolymer of polycyclic alicyclic alkyl(meth)acrylate or a copolymer of the polycyclic alicyclic alkyl(meth)acrylate and various (meth)acrylate-based monomers is proposed (for example, see Patent Documents 2 and 3). Both of a homopolymer and a copolymer of the polycyclic alicyclic alkyl(meth)acrylate disclosed in Patent Documents 2 and 3 have been improved in their heat resistance and thermal stability as compared with the heretofore used polymethyl(meth)acrylate. However, the degree of improvement is small, and their practical properties are not sufficient. Consequently, the development of a polymer that is excellent in heat resistance and thermal stability has been strongly requested in the field of the material of a resin for an optical component.    [Patent Document 1] JP 2002-105131 A    [Patent Document 2] JP 07-17713 B    [Patent Document 3] JP 06-208001 A